Control switch



R. F. KNEISLEY CONTROL SWITCH Nov. 29, 1938.

Filed Jan. 28, 1957 Nov Patented Nov. 29, 1938 PATENT OFFICE CONTROLswrron Richard F. Kneisley, Toledo, Ohio, assignor to The American FloorSurfacing Machine Company, Toledo, Ohio, a corporation of OhioApplicaticn January 28, 1937, Serial No. 122,682

3 Claims.

This invention relates particularly to electric switch controls forportable machines.

In the use of small hand-controlled machines of this type, such forinstance as vacuum cleaners, floor surfacing machines, or the like, theyare frequently tipped sideways for one purpose or another, and when sotipped it is desirable to have the operation of the associated electricmotor discontinued and then started again when the machine is rotatedand to havethis accomplished automatically without any attention on thepart of the operator.

The object of this invention is the provision of a simple, effective andeconomical control switch easily operated to close the associated motorcircuit and is adapted to automatically break such circuit upon apredetermined sidewise tipping in either direction of the associatedmachine and to again close the circuit when the machine is righted.

One embodiment of the invention is fully described in the followingspecification, and illustrated in the accompanying drawing, in which--Figure 1 is an elevation of a portion of a control handle equipped witha switch embodying the invention, parts of which handle being brokenaway and the switch being shown in off position; Fig. 2 is a section onthe line 22 in Fig. 1; Fig. 3 is a similar section with the switch in onposition; Fig. 4 is a section on the line 44 in Fig. 1; Fig. 5 is asimilar section with the switch turned to on position, and Fig. 6 is adiagram of the switch circuit and associated machine.

Referring to the drawing: l designates a small portable machine of anytype having a control handle 2 projecting therefrom. The handle 2 ispreferably hollow .to permit the extension of circuit lead wirestherethrough and is provided at its outer end with a hollow head 3.

A horizontally disposed shaft 4 is extended transversely through thehead 3, having bearings in its side walls, and is provided at each sideof the head with a handle member 5 to facilitate gripping and turning bythe operator.

Two tubes B and I, each containing a quantity of mercury 8, are mountedon the shaft 4 crosswise thereof within the head 3 and, in the presentinstance on opposite sides of the shaft, by clamps 9 each secured to theshaft by a screw Ill.

Each tube has two spaced contacts l2 at one end interposed in anelectric circuit l4, as well understood in the art. The lead wires I4,when connected up to a source of electrical supply, and both sets ofcontacts of the control switch are of this character, of the mercurytype, which is the position shown in Fig. 3, which may be termed the onposition, the mercury has flowed to the contact end of each tube and thecircuit is closed therethrough. The tubes 6 and 1, as mounted on theshaft 4, are tilted in opposite directions lengthwise of the shaft axis,as best shown in Fig. 1, so that when the machine and its handle I aretipped sidewise in either direction a predetermined extent, the mercurywill flow from the contact end to the other, and then lower, end of oneor the other of said tubes, and break the operating circuit.

One hand grip 5 is provided with a drum member 20 which carries a lockpin 2| and encloses a stationary catch member 22, which is attached tothe head 2. The pin 2| is normally pressed outward by a spring 23 andhas a knob at its inner end adapted to engage back of a catch lip 24 onthe member 22. When the associated hand grip 5 is turned incounterclockwise direction (Fig. 4) sufiicient to release the engagementof the pinknob with the catch lip 24, the pin springs outwardand thehand grip and shaft may then be turned in clockwise direction until thepin strikes the stop lug 25, as shown in Fig. 5, which is the onposition of the switch when the handle l is in normal position.

The shaft 4 is normally held turned to its off position by a coiledcontractile spring 30, one end of which is attached to the side of theshaft within the head 2 while the other end is fixed at a point withinthe outer end portion of the handle I. It is apparent from the foregoingthat in the use of the present switch, the mercury tubes 6 normallystand with their contact ends uppermost so that the mercury is ininoperative position within the bottoms of the tubes, as shown in Figs.1 and 2, the carrying shaft for the tubes being held in such normal 01fposition by the action of the spring 30. When it is desired to close theswitch circuit, the operator turns the shaft 4 in clockwise directionwith reference to Figs. 2 and 3, so as to tip the mercury tubes todispose their contact ends lowermost and to cause the mercury to flow tosuch ends and close the switch contacts. The switch is held in such onposition by the operator and as soon as the hand grips 5 are released,the switch will be returned by the action of the spring 30 to offposition. Upon a tipping of the handle 2 in either direction lengthwiseof the shaft 4 a predetermined extent, the mercury in one or the otherof the tubes will flow to the non-contact end thereof, due to theopposed tilting of the tubes on the shaft and thus cause an opening ofthe circuit which again automatically closes upon a return of the handleto normal position.

I wish it understood that my invention is not limited to any specificconstruction, arrangement or form of the parts, as it is capable ofnumerous modifications and changes without departing from the spirit ofthe claims.

Having thus described my invention, what I claim as new, and desire tosecure by United States Letters Patent, is:

1. In combination, a control handle for portable electric drivenmachines, a cross-shaft rotatably carried by said handle and forming ahand grip, an electric operating circuit, switch means in said circuitincluding two mercury containing tubes mounted with their axes crosswiseof the shaft and each having spaced contacts at the corresponding endsof said tubes disposed in said circuit, whereby the circuit is closedwhen the shaft is turned to place the contact ends of the tubeslowermost, said tubes being tilted lengthwise of the shaft, whereby whenthe tubes are in circuit closing position and the shaft is tippedlengthwise a predetermined distance in either direction ,the mercurywill flow away from the contact end of one or the other of the tubes andopen the circuit, and means normally holding the shaft turned in opencircuit position.

2. In combination, a control handle for portable electric drivenmachines, a cross-shaft rotatably carried by said handle, an electricoperating circuit, and switch means in said circuit including twomercury containing tubes mounted on the shaft and having their axescrosswise of the shaft parallel to a plane intersecting the axis of theshaft lengthwise thereof and each tube having spaced contacts at acorresponding end thereof and disposed in said circuit, whereby thecircuit is closed when the shaft is turned to place the contact ends ofthe tubes lowermost, said tubes being tilted lengthwise of the shaftwith their contact carrying ends remote from each other whereby when thetubes are in circuit closing position and the shaft is tipped lengthwisea predetermined extent in either direction the mercury will flow awayfrom the contact end of one or the other of the tubes and open thecircuit.

3. In combination, a control handle for portable electric drivenmachines having a casing at its outer end, a cross-shaft rotatablyprojecting through said casing, an electric operating circuit, switchmeans in said circuit disposed within said casing and including twomercury containing tubes mounted with their axes crosswise of the shaftwith one tube fixed to one side and the other tube to an opposite sideof the shaft and each having spaced contacts at the corresponding endsdisposed in said circuit, whereby the circuit is closed when the shaftis turned to place the contact ends of the tubes lowermost, said tubeshaving their axes disposed in planes parallel to an axial plane of theshaft and being oppositely tilted lengthwise of the shaft with theircontact carrying ends more remote whereby when the tubes are in circuitclosing position and the shaft is tipped lengthwise a predetermineddistance in either direction the mercury will flow away from the contactend of one or the other of the tubes and open the circuit, and meansnormally holding the shaft turned in open circuit position.

RICHARD F. KNEISLEY.

